Gas burner units for wall installation in furnaces and kilns



Oct. 7, 1969 R. s. SHEEHAN 3,471,247

GAS BURNER UNITS FOR WALL INSTALLATION IN FURNACES ANS KILNS Filed Nov. 15, 1967 2 Sheets-Sheet 1 INX'ENTOR. Richard S. Sheeh an ATTORNEY Oct. 7, 1969 R. s. SHEEHAN 3,471,247

GAS BURNER UNITS FOR WALL INSTALLATION IN FURNACES AND KILNS Filed Nov. 15, 1967 2 Sheets-Sheet INVENTOR. 5 Richard Sheehan A TTORNEY United States Patent 3,471,247 GAS BURNER UNITS FOR WALL INSTALLATION 1N FURNACES AND KILNS Richard S. Sheehan, 1672 S. Elizabeth St., Denver, Colo. 80210 Filed Nov. 15, 1967, Ser. No. 683,352 Int. Cl. F23d 13/12 U.S. Cl. 431347 4 Claims ABSTRACT OF THE DISCLOSURE A first refractory block having a plurality of internal, parallel gas passages, simultaneously feeding gas into a narrow transversally-extending burner slot and a second refractory block having a longitudinally-extending, flame-spreading protuberance positioned in a furnace wall in the path of a flame discharging from said burner slot for heating the wall to a radiating temperature.

This invention relates to gas-fired furnaces, such as employed in smelters, cement plants, and ceramic kilns of the type described in applicants prior Patent No. 3,208,504.

In usual contructions of this type, the gas burner flames are projected directly into the open body of the fire box of the furnace and the combustion takes place in the open body cavity in close association with the materials being fired. The result is an uneven distribution of maximum-heat-points of the flames over the product, resulting in uneven firing, and erratic chemical changes in the combustion gases and the product due to the non-uniform oxidation and reduction effects of the open flames.

The principal object of this invention is to provide a preformed burner unit structure in which the combustion will be completed in open cavities in the inner wall of the furnace so that the product being fired will be heated by emissivity from the cavities and from the surrounding walls to avoid the deleterious effects created by contact of the product with open flames and their surrounding gaseous envelopes.

A further object is to perform the elements of the burner unit structure of refractory material in sizes and shapes to conform to the modular dimensions of convensional fire brick so that the units can be conveniently interfitted directly into each other and into the fire bricks of the walls of furnaces of various types, sizes and shapes to uniformly heat the entire internal surfaces of the surrounding walls of the fire box so that the product will be fired by thermal radiation from the inner surfaces of the surrounding walls.

Other objects and advantages reside in the detail construction of the invention, which is designed for simplicity, economy, and efficiency. These will become more apparent from the following description.

In the following detailed description of the invention, reference is made to the accompanying drawing which forms a part hereof. Like numerals refer to like parts in all views of the drawing and throughout the description.

In the drawing:

FIG. 1 is a plan view of a molded refractory burner block as used in the burner unit structures of this in-' vention;

FIG. 2 is an elevational view of the burner block looking in the direction of the arrow 2 in FIG. 1;

FIG. 3 is a cross section through the burner block taken on the line 3-3 of FIG. 1;

FIG. 4 is a side, elevational view of a molded refractory, flame-spreader brick as used in the erection of the burner unit structure of this invention;

FIG. 5 is an elevational view of the forward flamespreading edge of the brick of FIG. 4;

FIG. 6 is an outside elevational view of a cup-shaped gas manifold as employed herein;

FIG. 7 is a cross-section through the manifold, taken on the line 7-7, FIG. 6;

FIG. 8 is a cross-section through the fire box of a given furnace showing how the elements shown in FIGS. 1-7 may be incorporated in the end wall thereof;

FIG. 9 is a fragmentary longitudinal section taken on the line 99, FIG. 8; and

FIG. 10 is a similar fragmentary section taken on the line 1010, FIG. 9.

The furnace may be. of any size and shape with the improved burner units of this invention embedded in the fire box walls at selected positions on the sides, ends or ceiling as required for maintaining the inner wall surfaces at a given, uniform temperature.

The burner unit structures are similar and each comprises an assembly of: one or more burner blocks 12 (as shown in FIGS. 1, 2, and 3); a plurality of flamespreader bricks 13 (as shown in FIGS. 4 and 5); and a plurality of separator bricks 14 similar to conventional (9" x 4 /2" x 2 /2") fire bricks.

The burner blocks 12 are premolded from a refractory composition capable of withstanding the temperatures to be encountered in the given furnace, to form a relatively flat rectangular block preferably having a length of 13 /2", a width of 12', and a thickness of 4 /2". An elongated, longitudinally-extending, V-shaped burner notch 15 is molded or indented in one face of the block 12 parallel to, and in spaced relation (preferably 2%") from the front edge of the latter. The notch 15 is of less length (preferably 11") than the block and is medially spaced longitudinally thereof. An exceedingly narrow (preferably .06) flame slot 16 is formed or cut into the block, at the apex of the V, for the full length of the latter. Gas is fed into the slot 16 from a plurality of parallel, equi-spaced feeder passages 17 which open to the slot 16 at their forward extremities and terminate in enlarged entrances 18 at the rear edge of the block. The periphery of the rear face of the block is chamfered, as shown at 19, to receive the flange of a metallic, rectangular, cup-shaped manifold 20 provided with a medially positioned gas inlet nipple 21 to which fuel gas is conducted in any desired manner to uniformly supply all of the feeder passages 17.

The flame spreader bricks 13 conform in size to a conventional fire brick except that one side edge is inset, depressed, or cut-back adjacent one extremity of the brick, as indicated at 22, to provide a V-shaped, flamespreading point 23 on the remainder of the latter side edge.

An example of a typical installationof a burner unit structure in a wall of a fire box of a selected furnace is illustrated in FIGS. 8, 9 and 10. The latter fire box is provided with: side walls, as indicated by side wall bricks 24; a floor, as shown by floor bricks 25; and a roof, as indicated by roof bricks 26.

To install one of the burner units as an end wall in the latter fire box, one of the burner blocks 12 is positioned transversally across the extremity of the floor in horizontal alignment with the floor bricks 25, as shown in FIG. 9, and a lower row of alternating flame spreader bricks 13 and separator bricks 14 is positioned vertically on the burner block 12 with the front edges of the separator bricks 14 and the cut-back portions 22 of the spreader bricks aligning wtih the slot 16, as shown in FIG. 10, and with the flame spreading points 23 directed downwardly.

An upper, similar row of alternating spreader bricks 13 and separator bricks 14 is now vertically positioned on the first row with the flame spreading points 23 directed upwardly as shown in FIG. 8, and a second burner block 12 is placed on the second row with its flame slot 16 in alignment with the front surfaces of the separator bricks 14 and with the cut-back portions 22 of the flame spreader bricks 13. The end wall is now completed by filling in with conventional fire bricks 27. The manifolds 20 are now installed in the chamfers 19 of the burner blocks 12 and the inlet nipples 21 are connected with a source of fuel gas. The unit is now ready for use.

It can be seen that the fuel gas will discharge from each burner block in a wide ribbon of gas positioned directly forward of, and in contact with, the flat wall surface formed by the separator bricks 14 and the cutback portions 22 of the flame spreader bricks 13. The entering ribbons of gas will be divided into uniform sections by the flame spreading points 23 and will be compressed in the channels between the protruding portions of the flame spreader bricks 13 where complete combustion will take place. Attention is called to the fact that the maximum heat portion of each wide ribbon-like flame setcion will be in close proximity to the end wall surface and confined between the protruding portions of the spreader bricks. Heat will, of course, be radiated directly into the fire box from the wide confined flames and from reflection from the separator bricks 14. However, the major portion of the heat entering the fire box will be by emissivity from the protruding surfaces of the flame spreader bricks 13 and the forward surfaces of the separator bricks 14 both of which will reach a temperature approaching the complete combustion temperature of the flames. It will be noted that there is no contact between the flame gases and the product being fired and the deleterious effects of oxidation and scale formation are eliminated.

The illustrated construction shown in FIGS. 8 and 9 embodies only two burner blocks. The blocks, however, can be placed end to end to produce a wall flame of any desired length and can be placed back to back to produce wall flames over any desired wall areas. Some thermal results could be obtained by placing the conventional inner fire brick wall of the fire box on the burner block in alignment with and in close proximity to the flame slot without the flame-spreader blocks. The wall would be heated by the wide flame ribbon exiting from the flame slot but the increased efliciency obtained by the flame confinement, the increased radiation surface and the perfect combustion produced by the protruding portions of the flame spreading bricks would be lost.

In FIGS. 8, 9 and 10, two burner blocks, one directed upwardly and one downwardly, and two rows of flame spreader bricks have been used. In some positions in some fire box walls, a single burner block and a single row of flame spreader bricks might be more practical. Also in FIGS. 8, 9 and 10, the burner blocks are positioned horizontally and the spreader bricks have been positioned vertically. This is simply for the purpose of illustration. In actual practice, these elements will be positioned to best suit the furnace construction. Conformity with vertical or horizontal positioning is inconsequential.

While a specific form of the invention has been described and illustrated herein, it is to be understood that the same may be varied within the scope of the appended claims, without departing from the spirit of the invention.

Having thus described the invention, what is claimed and .ldesired to be secured by Letters Patent is:

:close proximity to the inner surface of said wall comprising:

(a) a block of refractory'material having an elongated notch in one of its surfaces;

(b) a plurality of gas feeder passages in said block extending from a second surface of said block and individually communicating with said notch to supply gas thereto;

means for simultaneously feeding gas to said gas feeder passages;

(d) a flame slot extending from said notch into said block throughout the length of said notch, said gas feeder passage terminating at said slot in spacedapart relation therealong to uniformly distribute the streams of gas discharging from said feeder passages throughout the length of said notch to produce a wide ribbon-like stream of gas;

(e) a plurality of flame spreader bricks, one extremity of the inner edge of each brick being set back from the remainder of that edge, said set-back extremities being positioned against said block in alignment with the flame slot of said block; and

(f) a plurality of separator bricks individually positioned between said flame spreader bricks with their inner edges aligned with the set-back extremities of the spreader bricks to allow the non-set-back portions of the inner edges of said flame spreader bricks to protrude over said slot to divide the wide ribbonlike stream of gas into separated portions.

2. A gas burner unit as described in claim 1 having wedge-shaped points formed on the non-set-back portions of said spreader bricks adjacent the set-back portions thereof to exert a separating and spreading action on the gas arising from said flame slot.

3. A gas burner unit for insertion in the wall of a fire box comprising:

(a) a plurality of flame spreader bricks, one extremity of one longitudinal edge of each of said flame spreader bricks being set back from the remainder of that edge, said set-back extremities being positioned in alignment with each other;

(b) a plurality of separator bricks individually positioned between said flame spreader bricks with their inner edges aligned with the set-back extremities of the spreader bricks to allow the non-set-back portions of the inner edges of said flame spreader bricks to protrude forwardly from the plane of said separator bricks to provide combustion channels between the non-set-back portions of the adjacent spreader bricks; and

(c) means for introducing and directing a flame over said separator bricks and longitudinally of said channels.

4. A gas burner unit as described in claim 3 having 55 wedge-shaped extremities on said non-set-back portions to direct said flame into said channels.

References Cited UNITED STATES PATENTS 2,581,075 1/1952 Buck 431-353XR 3,208,504 9/1965 Sheehan 431-176 FOREIGN PATENTS 1,295,509 5/1962 France. 127,990 1959 Russia.

FREDERICK L. MATTESON, JR., Primary Examiner HARRY B. RAMEY, Assistant Examiner 

